Most commercially available high voltage defibrillator testers are limited in their ability to test multiple high voltage defibrillators. For example, a manual high voltage defibrillator tester system is typically configured to support twelve modules synchronously with parallel port communications. Since parallel port communications are used, the high voltage defibrillator tester can only test one product type at a time. Generally, it takes about 135 minutes to test twelve devices. It is therefore desirable to develop high voltage defibrillator testers that overcome this limitation.